GENETIC DIVERSITY, CORRELATION AND PATH ANALYSIS IN STEM AMARANTH (Amaranthus lividus L.)

Abstract

An experiment was conducted with the aim of assessments of genetic diversity, correlation and path analysis in stem amaranth (Amaranthus lividus L.).In this experiment thirty-seven stem amaranth genotypes were used as experimental materials. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Variability, mean performance, correlation matrix, path analysis and genetic diversity analysis was performed. Analysis of variance revealed significant genotypic variation. Phenotypic co-efficient of variation (PCV) was higher than genotypic co-efficient of variation (GCV) for all the characters studied due to the influence of environment. High PCV and GCV was observed for plant gross weight, stem weight, ten leaf weight, plant height, stem height, stem diameter, number of branch per plant,number of leaves per branch, root shoot ratio, stem dry weight and plant weight without root indicating high variability among the genotypes and substantial scope of improvement in these traits in present material through selection. High heritability along with high genetic advance as percent of mean was observed for days to first flowering, days to 50% flowering, ten leaf weight, stem diameter, number of branch, number of leaves per branch, stem dry weight and plant weight without root. Hence, these characters need to be given more importance in selection as these are expected to be controlled by additive genes.Correlation revealed that plant weight without root had positive association with days to first flowering, days to fifty percent flowering, plant gross weight, stem weight, plant height, stem height, leaf length, leaf breath and stem diameter both at phenotypic and genotypic level. So, selection based on these traits would give better response for the improvement in yield in stem amaranth. Path analysis revealed that days to first flowering, plant gross weight, stem weight, ten leaf weight, plant height, stem height, leaf length, leaf breadth, stem diameter, number of branch, root shoot ratio, stem dry weight and thousand seed weight had positive direct effect on plant weight without root indicating these were the main contributors to yield per plant. Considering this diversity pattern, genetic status and other agronomic performances, G26, G25, G34, G36, G32 and G35 may perform better parents for efficient hybridization programme and the characters, days to first flowering, stem weight, stem height, stem breadth, number of branch, stem dry weight and thousand seed weight contributed maximum divergence among the stem amaranth genotypes.